Revert "audio/wavcapture: Clarify licensing"

This reverts commit 456a84d1.

This patch wasn't submitted to the list and did not get Acked by other
copyright holders in the file.
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

audio/wavcapture.c

-/* public domain */
 #include "hw/hw.h"
 #include "monitor.h"
 #include "audio.h"